> I think you might be confusing tactical and strategic nuclear weapons. As far as I know strategic weapons are only for protecting their sovereignty and the use of tactical weapons is potentially more flexible.

I don't believe their doctrine makes a distinction, because the rest of the world would not make a huge distinction.

Im happy to be wrong thought if you could link a primary source.

I’m only directly aware of speculation with regard to there being a possible distinction such as https://www.bbc.com/news/world-60664169

I don't see that as being a distinction but more Russia just rattling the nuclear sabre.

They have been doing it since the start of the war and do it about every single large shipment of weapons to Ukraine.

I suspect its mostly for a internal audience but also to make the west scared to send weapons which clearly hasn't worked.

Russia (and before that, the USSR) viewed nuclear weapons as just another form of artillery. The US did as well, between Davey Crockets, SADM, Pershing 2 and GLCM.

The US doesn’t differentiate between those two cases, and thus a “tactical” strike from the Russian pov would lead to a massive escalation.

Putin should remember that US doctrine explicitly approves massive nuclear first strikes when a situation appears to be escalating to nuclear conflict. Plus the US actually has thousands of mission-ready nukes and only two cities to hit.